Fabrication of Easy Separable and Reusable Adsorbent Composite based on MIL-125/MIL-53 Binary MOF/CNT/Alginate Microbeads for Aremoval of Tetracycline from Water Bodies

Abstract During the turbulent period of COVID-19, the medical staff is exerting great efforts to preserve humanity. However, the tons of pharmaceutical residues especially antibiotics that is being disposing daily into water bodies may be the seed to an even more ferocious pandemic. Thence, it is inevitable to find out effective strategies for removing these noxious pharmaceutical residues from water. We aimed in this investigation to fabricate easy separable composite microbeads for efficient adsorption of tetracycline (TC) drug. Herein, MIL-125/MIL-53 binary metal organic framework (MOF) was synthetized and incorporated with carbon nanotube (CNT) into alginate (Alg) microbeads to form MIL-125/MIL-53/CNT@Alg composite microbeads. Various tools including FTIR, XRD, SEM, BET, Zeta potential and XPS were applied to characterize the composite microbeads. The results revealed that the adsorption of TC was augmented with rising TC proportion up to 15 wt% in the microbeads matrix. In addition, the adsorption process followed the pseudo-second-order and well-fitted to Freundlich and Langmuir models with a maximum adsorption capacity of 294.12 mg/g at 25 ◦C, while the adsorption process was endothermic, randomness and spontaneous. Besides, reusability test signified that MIL-125/MIL-53/CNT@Alg composite microbeads retained admirable adsorption properties for six consecutive cycles, emphasizing its potentiality for removing of pharmaceutical residues.